Light control systems have been used to control light fixtures in various environments, such as office buildings, retail stores, hospitals, schools, factories, and the like. In light control systems that include multiple light fixtures and multiple light controllers, there generally needs to be a way to assign which light fixtures are under control of which light controllers. There are several known approaches to making these assignments. One approach is to manually assign individual light fixtures to specific light controllers. However, this is a time consuming process that typically requires a person (e.g., an installer or user) to manually configure each light fixture to be assigned to a light control group or light controller. This time consuming process can include setting a group identifier (ID) on each light fixture, programming a unique light fixture ID into each light controller, or pairing a light fixture and a light controller through some combination of settings on both units. In more recent years, configurations of light control systems have become even more complex as these systems often also need to support control of the light levels based on additional information, such as occupancy information obtained from occupancy sensors and/or light level information obtained from light level sensors. Occupancy sensors (e.g., motion detection sensors) can be used, for example, to detect whether a space is occupied or empty, thereby enabling light fixtures to be selectively turned-off or dimmed when a space is empty. Light level sensors can be used, for example, to detect light levels within an environment, so that artificial light (produced by light fixtures) can be reduced when natural light (e.g., sunlight) is providing at least a portion of a desired level of light.
There have been significant efforts to use automation to improve the identification and assignment of light fixtures to light controllers. One approach involves commanding light fixtures, one at a time, to flash in order to identify themselves to a light controller. A drawback of this approach is that the flashing is visible perceptible as flicker, and thus, this approach does not lend itself to continuous or periodic use. Another approach involves adding additional dedicated infrared (IR) transmitters and receivers to light fixtures and light controllers, to allow the identification and assignment of light fixtures to light controllers to be made one at a time. Drawbacks of this approach are that only one light fixture can be identified and assigned to a light controller at a time, and additional IR transmitter electronics are required, which potentially increases costs.